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1.
李子平 《中国物理 C》2002,26(12):1214-1222
基于高阶微商奇异拉氏量系统的相空间生成泛函,导出了定域和非定域变换下的量子正则Noether恒等式;对高阶微商规范不变系统,导出了位形空间中定域和非定域变换下的量子Noether恒等式.指出在某些情形下,由量子Noether恒等式可导致系统的量子守恒律.这种求守恒律的程式与量子Noether(第一)定理不同.用于高阶微商非AbelChern-Simons(CS)理论,求出某些非定域等变换下的量子守恒量.  相似文献   

2.
基于奇异拉氏量系统Green函数的相空间生成泛函,导出了相空间中整体变换下的Ward恒等式和整体对称下的量子守恒律.一般它有别于经典Noether守恒律.用于杨-Mills理论,导出了BRS变换下的Ward-Takahashi恒等式和BRS守恒律;用于非Abel-Chern-Simons理论,导出了系统的量子角动量,它有别于经典角动量在于计及了鬼粒子对角动量的贡献.  相似文献   

3.
李子平 《中国物理 C》1988,12(6):782-785
考虑非不变作用理系统在无限连续群下的变换性质,导致了广义Noether恒等式,由此可导出系统的强守恒律和弱守恒律,给出与此相联系的重质量杨-Mills场守恒的PBRS荷,它有别于守恒的BRS荷.讨论了变更性系统的Dirac约束.  相似文献   

4.
李子平 《中国物理 C》1995,19(11):1012-1018
分别从正规和奇异拉氏量系统的相空间生成泛函出发,导出了增广相空间中整体对称下的正则形式Ward恒等式.考虑对应的定域交换,得到了量子水平的守恒荷,给出了正则形式的量子Noether定理.讨论了在核子和π介子相互作用中的初步应用.  相似文献   

5.
李子平 《中国物理 C》1995,19(4):320-326
从系统的作用量在普遍的定域和非定域变换下的性质出发,导出了含非定城变换的广义Noether恒等式.将其用于高阶微商杨—Mills场论,求出了有别于BRS荷的新PBRS守恒荷和非定域变换下的新守恒荷.  相似文献   

6.
规范理论中的量子守恒荷   总被引:2,自引:0,他引:2  
从Faddeev-Popov(F-P)方法对规范理论导致的位形空间生成泛函出发,导出了规范系统在量子情形下的守恒律,用于非Abel Chern-Simons(CS)理论,得到了CS场与Fermi场耦合系统的量子BRS守恒荷和量子守恒角动量. 对CS理论中的分数目旋性质给予了讨论.  相似文献   

7.
分别从Faddeev–Popov(FP)和Faddeev–Senjanovic(FS)路径积分量子化方法对高阶微商规范不变系统导致的位形空间和相空间生成泛函出发,导出规范系统在量子水平下的守恒律,用于高阶Maxwell非AbelChern–Simons(CS)理论.得到了高阶Maxwell非AbelCS理论与标量场耦合系统的量子BRS守恒荷和量子守恒角动量,无论从位形空间或相空间的生成泛函出发,其结果是相同的.并对CS理论中的分数自旋性质给予了讨论.  相似文献   

8.
李子平 《物理学报》1996,45(10):1601-1608
从奇异拉氏量系统相空间路径积分的量子化形式出发,导出了系统在增广相空间整体变换下的广义正则Ward恒等式和量子水平的守恒荷,一般这些守恒荷有别于经典Noether荷.给出了在杨-Mils场论中的应用,找到了新守恒荷  相似文献   

9.
奇异位氏量系统的整体量子正则对称性质   总被引:1,自引:1,他引:0       下载免费PDF全文
李子平 《物理学报》1996,45(10):1601-1608
从奇异拉氏量系统相空间路径积分的量子化形式出发,导出了系统在增广相空间整体变换下的广义正则Ward恒等式与量子水平的守恒荷,一般这些守恒荷有别于经典Noether荷。给出了在场-Mills场论中的应用,找最新守恒荷。  相似文献   

10.
光孤子约束系统的量子场论   总被引:1,自引:1,他引:0  
光孤子系统可用奇异Lagrange量描述,系统含Dirac约束.通常按对应原理写出系统对易关系和量子运动方程时,未计及约束.文中对该系统进行严格的Dirac括号量子化,给出了系统的对易关系和量子运动方程,还对系统进行了路径积分量子化,并根据量子水平的Noether定理,导出了系统在时空平移变换不变性下的量子能量和动量守恒.系统还具有相位变换下的不变性,相应导出了系统的粒子数守恒.  相似文献   

11.
Based on the phase-space path integral (functional integral) for a system with a regular or singular Lagrangian, the generalized Ward identities for phase space generating functional under the global transformation in phase space are derived respectively. The canonical Noether theorem at the quantum level is also established. It is pointed out that the connection between the symmetries and conservation laws in classical theories, in general,is no longer preserved in quantum theories. The advantage of our formulation is that we do not need to carry out the integration over the canonical momenta as usually performed. Applying the present formulation to Yang-Mills theory, the quantal BRS conserved quantity and Ward-Takahashi identity for BRS tranformation are derived; the Ward identities for gaugeghost proper vertices and new quantal conserved quantity are also found. In comparison of quantal conservation laws with those one deriving from configuration-space path integral using the Faddeev-Popov(F-P) trick is discussed. A precise study of path-integral quantisation for a nonlinear sigma model with Hopf and Chern-Simons (CS) terms is reexamined. It has been shown that the angular momentum at the quantum level is equal to classical (Noether ) one. Applying our formulation to non-Abelian CS theory, the quantal conserved angular momentum of this system is obtained which differs from classical one in that one needs to take into account the contribution of angular momenta of ghost fields.  相似文献   

12.
Based on the phase-space generating functional of the Green function for a system with a regular/singular Lagrangian, the quantal canonical Noether identities (NI) under the local and non-local transformation in extended phase have been derived, respectively. The result holds true whether the Jacobian of the transformation is equal to unity or not. Based on the configuration-space generating functional of the gauge-invariant system obtained by using Faddeev-Popov (FP) trick, the quantal NI under the local and non-local transformation in configuration space have been also deduced. It is showed that for a system with a singular Lagriangian one must use the effective action in the quantal NI instead of the classical action in corresponding classical NI. It is pointed out that in certain cases, the quantal NI may be converted into the quantal (weak) conservation laws by using the quantal equations of motion. This algorithm to derive the quantal conservation laws differs from the quantal first Noether theorem. The preliminary applications of this formulation to Yang-Mills (YM) fields and non-Abelian Chern-Simons (CS) theories are given. The quantal conserved quantities for non-local transformation in YM fields are obtained. The conserved BRS and PBRS quantities at the quantum level in non-Abelian CS theories are also found. The property of fractional spin in CS theories is discussed. PACS no11.10. Ef; 11.30.−j 11.15. −q.  相似文献   

13.
Based on the configuration-space generating functional of the Green functions for the gauge-invariant system in higher-order derivatives theories, the equations of the transformation properties at the quantum level have been derived. It follows that the sufficient conditions are found which implies that there exists the conservation laws and the expressions of the quantal conserved laws are also given. Applying the results to the non-Abelian Chern-Simons higher-order derivatives theories, the quantal BRST conserved charge and other conserved charges are found, the transformation properties of the conformal transformation at the quantum level is discussed, the quantal conserved angular momentum is derived, it is pointed out that fractional spin in this system may be also preserved in quantum theories. But the connection between the symmetries and conservation laws in classical theories are not always preserved in quantum theories.  相似文献   

14.
Based on the phase-space generating functional of the Green function for a system with a regular/singular higher-order Lagrangian, the quantum canonical Noether identities (NIs) under a local and non-local transformation in phase space have been deduced, respectively. For a singular higher-order Lagrangian, one must use an effective canonical action IeffP in quantum canonical NIs instead of the classical IP in classical canonical NIs. The quantum NIs under a local and non-local transformation in configuration space for a gauge-invariant system with a higher-order Lagrangian have also been derived. The above results hold true whether or not the Jacobian of the transformation is equal to unity or not. It has been pointed out that in certain cases the quantum NIs may be converted to conservation laws at the quantum level. This algorithm to derive the quantum conservation laws is significantly different from the quantum first Noether theorem. The applications of our formulation to the Yang-Mills fields and non-Abelian Chern-Simons (CS) theories with higher-order derivatives are given, and the conserved quantities at the quantum level for local and non-local transformations are found, respectively.Received: 12 February 2002, Revised: 16 June 2003, Published online: 25 August 2003Z.-P. Li: Corresponding authorAddress for correspondence: Department of Applied Physics, Beijing Polytechnic University, Beijing 100022, P.R. China  相似文献   

15.
Quantal global symmetry for a gauge-invariant system   总被引:1,自引:0,他引:1  
Based on the configuration-space generating functional obtained by using the Faddeev-Popov trick for a gauge-invariant system, the Ward identities for global transformation are derived. The conservation laws at the quantum level for global symmetry transformation are also deduced. A preliminary application of the present formulation to non-Abelian Chern-Simons (CS) theory is given. The Ward identity and quantal BRS charge under the BRS transformation are deduced. The quantal conserved angular momentum is obtained and the fractional spin for CS theories is discussed.  相似文献   

16.
张莹  李子平 《物理学报》2005,54(6):2611-2613
与经典水平下的研究不同,研究了(2+1)维含非Abel Chern-Simons 项的非线性σ模 型量子水平的分数自旋性质.根据约束Hamilton系统的Faddeev-Senjanovic(FS)路径积分量 子化方案,对该系统进行量子化,由量子Noether定理给出了量子守恒角动量,说明了在量子 水平上该系统仍具有分数自旋的性质. 关键词: 约束Hamilton系统 分数自旋 O(3)非线性σ模型  相似文献   

17.
The fractional spin of a system with Chern–Simons (CS) term coupled to a polaron at the quantum level is studied. The Faddeev–Senjanovic (FS) scheme for path-integral quantization of constrained Hamiltonian systems is applied. The quantal conserved angular momentum and the fractional spin at the quantum level of this system are presented based on the quantal Noether theorem. The fractional spin is also presented for the system with Maxwell kinetic term.  相似文献   

18.
The property of fractional spin of the system with Chern–Simons (CS) term coupled to polaron at the quantum level is studied. According to the rule of path integral quantization for constrained Hamiltonian system in Faddeev–Senjanovic (FS) scheme, this system is quantized. Based on the quantal Noether theorem, the quantal conserved angular momentum and the fractional spin at the quantum level of this system is presented. The fractional spin is also presented in the system including Maxwell kinetic term.  相似文献   

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